Communal clashes in Nigeria's southern Cross River State over land ownership have killed scores of people and displaced thousands, a government official said.

Cross River State Emergency Management Agency director-general John Inaku said about 150 people have been killed in the past week, and appealed for aid for the displaced.

State youth council chairman Prince Ndiyo said the toll was fewer than 100, mostly women and children, in fighting over ownership of a piece of farmland.

State police commissioner Hafiz Inuwa said peace has been restored and additional security deployed.

Such fighting is common in Nigeria's south, where many are killed over farmland disputes. About 20 people were killed in June over land disputes between a Cross River State community and a neighbouring Ebonyi State settlement.